A kind of method of utilizing fluid-bed fly ash to be equipped with metallurgical-grade aluminum oxide
Technical field
The present invention relates to a kind of technology of production metallurgy grade aluminum oxide, being specifically related to a kind of is raw material with the circulating fluid bed coal ash, through the technology of one step of associating removal of impurities acid pasting direct production metallurgical-grade aluminum oxide.
Background technology
Flyash is the waste that the coal-burning power plant discharges; China is to be the country of main energy sources with coal; Annual flyash from power plant emission is up to more than one hundred million tons; A large amount of soils are are not only occupied in the discharging of flyash, and serious environment pollution, how to handle and utilize flyash to become an important problems.On the other hand; Contain multiple utilizable component in the flyash; Research shows, contains the aluminum oxide of 30-50% in the circulating fluidized bed ash usually, in bauxite resource poor day by day today; From flyash, extracting aluminum oxide is the effective way that makes flyash turn waste into wealth, fully utilize, and has good social benefit and economic benefit.
Flyash can be divided into coal-powder boiler flyash and circulating fluid bed coal ash according to the difference of calcination condition.Coal-powder boiler flyash generates through high temperature (1400-1600 ℃) burning, and alumina component wherein is the mineral forms of vitreous state or high temperature aluminum-containing mineral mullite crystal, corundum crystal and exists, and stability is very high; And circulating fluidized bed ash temperature of combustion is about 850 ℃, and more traditional coal dust ashes temperature of combustion reduces greatly.The difference of temperature of combustion has determined circulating fluidized bed ash and the traditional essential difference of coal-powder boiler flyash in the thing phase composite: its main thing phase composite is amorphous metakaolinite, and silicon-dioxide wherein, aluminum oxide and red stone etc. all have good active.
At present, from flyash, extract method of alumina and be broadly divided into alkaline process and acid system two big classes.Wherein alkaline process can be divided into Wingdale (soda-lime) sintering process and yellow soda ash sintering process again.
Wingdale (soda-lime) sintering process be with flyash with after Wingdale (soda-lime) mixes, at high temperature (1320-1400 ℃) calcining and activating, in this process, aluminum oxide in the flyash and silicon-dioxide generate calcium aluminate and Dicalcium Phosphate (Feed Grade) with the Wingdale reaction respectively.Product after the calcining is with after the sodium carbonate solution leaching, filtering, and calcium aluminate gets into solution with the form of sodium metaaluminate, behind desiliconization, carbon branch (or plant and divide), obtains white lake, and calcining at last obtains alumina product; Form the silico-calcium slag and filter the back Dicalcium Phosphate (Feed Grade), can be as the raw material of producing cement.All adopt Wingdale (soda-lime) sintering process or improved limestone sintering method technology like patent CN101070173A, CN101306826A, CN101049935A, CN10284668A, CN101302021A, CN101125656A, CN101041449A, CN1030217A, CN1644506A, CN101028936A, CN1548374A, CN101085679A, CN1539735A.The raw materials for sintering that the limestone sintering method is used is the Wingdale of cheapness, and manufacturing cost of aluminum oxide is reduced relatively.But there are a lot of defectives in this method: at first; When extracting aluminum oxide; Can produce a large amount of silico-calcium slags, 1 ton of aluminum oxide of every production will produce the silico-calcium slag about 8~10 tons, if the building materials market can not these silico-calcium slags of complete digestion; Will certainly cause waste discharge new, that the stacking amount is bigger, and silica composition does not obtain high value added utilization; Secondly, the limestone sintering method needs high-temperature calcination, belongs to energy processes, and the requirement of its technological process and equipment is also higher; The 3rd, alkali dissolves in the process excessive owing to the quantity of slag, and the recovery of alkali is reduced, and causes cost to rise.
The yellow soda ash sintering process is that flyash and yellow soda ash are calcined down at high temperature (750-1450 ℃).Aluminum oxide and silicon oxide in calcination process in the flyash are activated simultaneously; Therefore need further acidifying (through carbonation reaction or with sulfuric acid/hydrochloric acid reaction) sial is separated; Owing to adopted the technology of acid behind the first alkali; This method also is called as hybrid system, all adopts yellow soda ash sintering process technology like patent CN101041450A, CN101200298A, CN101172634A, CN101254933A.Compare with the limestone sintering method, the level of residue that the yellow soda ash sintering process produces is less, and the silica composition in the flyash has obtained value added applications.But, owing to calcining at high temperature, and need after the calcining further separate with the realization sial, so energy consumption to be higher with acid-respons, technological process is complicacy.
The above limestone sintering method and yellow soda ash sintering process all need flyash and Wingdale/yellow soda ash in the pyroreaction activation, and this method is suitable for the relatively poor coal-powder boiler flyash of reactive behavior.For the higher circulating fluid bed coal ash of activity, can be not activated directly with flyash and acid-respons.
Acid system is direct and acid solution reaction with flyash, obtains aluminum salt solution, then aluminium salt calcining and decomposing is prepared aluminum oxide.All adopt acid system from flyash, to extract aluminum oxide like patent CN1923695A, CN1920067A, CN101045543A, CN101397146A, CN1792802A, CN1927716A.Flyash carries out in the temperature that is lower than under 300 ℃ with the reaction of acid usually, compares with the high-temperature calcination of yellow soda ash sintering process with the limestone sintering method, and energy consumption reduces greatly.In addition since silicon-dioxide not with acid-respons, stay fully in the solid phase slag, and acid system can not introduce impurity such as calcium, sodium, can obtain the higher aluminum oxide of purity in theory.But the defective of acid system is in the process that acid is dissolved, and soluble impurity in the flyash such as iron etc. can get into solution, contains impurity such as more iron in the alumina product that makes acid system prepare, and is difficult to remove.Wherein a kind of terms of settlement is that the aluminum oxide that acid system obtains is used alkali dissolution, make aluminium change soluble sodium metaaluminate into and get into solution, and impurity such as iron forms precipitation of hydroxide, through the solid-liquid separation deironing.The back molten method of alkali is dissolved in this acid earlier makes complex manufacturingization, has also increased production cost.
Summary of the invention
To above technological deficiency, it is the method for feedstock production metallurgical-grade aluminum oxide with flyash that the present invention provides a kind of.Said method comprises:
A) flyash is crushed to below 100 orders, adds water and be mixed with the slurry that solid content is 20-40wt%,, iron in the flyash (in red stone) content is reduced to below the 1.0wt%, cross and filter filter cake through the wet magnetic separation deironing;
B) in filter cake, add hydrochloric acid and react, and through solid-liquid separation and washing, obtaining pH is the salt pickling liquor of 1-3;
C) the salt pickling liquor is carried out degree of depth deironing through the macroporous type cationic resin column, get refined crystalline aluminium chloride liquid;
D) refined crystalline aluminium chloride liquid is carried out concentrating under reduced pressure, crystallization is separated out in cooling then, and solid-liquid separation gets crystal aluminum chloride;
E) crystal aluminum chloride is calcined calcination time 1-4 hour at 900-1200 ℃; Or earlier crystal aluminum chloride was calcined 1-2 hour at 300-500 ℃, be warming up to 900-1200 ℃ of calcining 1-3 hour then, promptly get metallurgical-grade aluminum oxide.
In the step a) according to the invention, said flyash includes but not limited to circulating fluid bed coal ash, at first; Flyash is crushed to below 100 orders; Adding water, to be made into solid content be 20-40wt%, the slurry of preferred 30-35wt%, and iron (in the red stone) content that carries out in wet magnetic separation to the flyash through magnetic separator is reduced to below the 1.0wt%; Obtaining solid content through solid-liquid separation is 25-50wt%, is preferably the filter cake of 30-45wt%.
The equipment that wet magnetic separation deironing according to the invention is adopted can be selected the various magnetic plants that are suitable for the opaque Material deironing commonly used for use.
Said magnetic plant is preferably following vertical-ring magnetic separator, and this magnetic separator comprises: change, induction medium, upper yoke, lower yoke, magnet coil, opening for feed, mine tailing bucket and flushometer.Wherein, induction medium is installed in the change, and magnet coil is arranged on around upper yoke and the lower yoke; So that upper yoke and lower yoke become a pair of generation vertical direction field pole, said upper yoke and lower yoke are separately positioned on interior, the outer both sides of ring of ring of change below, wherein; Said induction medium is the Composite Steel expanded metals; Every layer of XPM weaved into by the silk stalk, and the edge of said silk stalk has rib shape wedge angle, and said upper yoke is connected with opening for feed; Said lower yoke is connected with the mine tailing bucket that is used for discharging, and said flushometer is positioned at the change top.
Preferably, said opening for feed is connected with the sidepiece of upper yoke.
Preferably, said vertical-ring magnetic separator also comprises refrigerating unit, and said refrigerating unit is arranged on all pressures chamber water jacket around the magnet coil.
Preferably, said XPM is processed by 1Cr17.
Preferably, said magnet coil is a double glass fiber bag enameled aluminium flat wire solenoid.
Preferably, the medium layer spacing of XPM is 2-5mm.
Preferably, the medium layer spacing of XPM is 3mm.
Preferably, the thickness 0.8-1.5mm of XPM, sizing grid are 3mm * 8mm-8mm * 15mm, silk stalk width 1-2mm.
Preferably, the thickness 1mm of XPM, sizing grid are 5mm * 10mm, silk stalk width 1.6mm.
Preferably, said vertical-ring magnetic separator also comprises pulsing mechanism, and said pulsing mechanism links to each other with the mine tailing bucket through the rubber eardrum.
The magnetic separation condition of said magnetic plant includes but not limited to field intensity 1.0-2.0 ten thousand GS, is preferably 1.5-1.75 ten thousand GS, electric current 30-40A.Said magnetic separation process can repeat 2-4 time, preferred 2-3 time.
In the step b) according to the invention; In the gained filter cake, adding concentration is 20-37wt%; The hydrochloric acid that is preferably 20-30wt% carries out acid and dissolves reaction, in the control hydrochloric acid in HCl and the flyash mol ratio of aluminum oxide be 4: 1-9: 1, be preferably 4.5: 1-6: 1; Wherein control reaction temperature is 100-200 ℃, is preferably 130-150 ℃; Reaction pressure is 0.1-2.5MPa, is preferably 0.3-1.0MPa; Reaction times is 0.5-4.0h, is preferably 1.5-2.5h, and again through solid-liquid separation and washing, obtaining pH value is the salt pickling liquor of 1-3.Said solid-liquid separation can adopt solid-liquid separating method commonly used, for example, uses sedimentation, filtration under diminished pressure, pressure filtration etc.
Conventional washing methods is adopted in said washing, and water washs sour molten slag.Said washing process can repeat more than 2 or 2 times, for example 2-4 time, to sour molten slag near neutrality till, for example, the pH value of sour molten slag is about 5~6.
The method of the invention c) in, said macroporous type resin cation(R.C.) can be selected D001 for use, and 732,742,7020H, 7120H, JK008 or SPC-1.
With the pickling liquor of step c) gained salt through the macroporous type cationic resin column further removing iron contamination wherein, thereby make refined crystalline aluminium chloride liquid.Wherein the salt pickling liquor is the conventional method in this area through the method for resin column; The present invention preferably adopts following method: at 20 ℃-90 ℃; Under preferred 60-80 ℃; The salt pickling liquor with 1-4 times of resin volume/hour, be preferably 2-3 times of resin volume/hour speed below the mode that goes out on advancing through resin column, solution is piston-like and upwards flows in the resin space.Resin column can adopt the mode of single-column or twin columns polyphone.
In the step d) according to the invention, step c) gained refined crystalline aluminium chloride liquid is carried out negative pressure concentrate, concentrating pressure is-0.03--0.07MPa to be preferably-0.04--0.06MPa; Thickening temperature is 50-110 ℃, is preferably 70-80 ℃.Liquid cooling after concentrating is separated out crystal aluminum chloride; The crystal weight that control is separated out when cooling accounts between the 40%-65% of the former weight of refined crystalline aluminium chloride liquid; So that most of aluminum chloride crystallization separates out, and impurity such as a small amount of iron(ic)chloride are still stayed in the middle of the solution because concentration is lower.
After separating out crystallization, carry out solid-liquid separation, and the residue mother liquor returns refined liquid condensing crystal again.When Recycling Mother Solution arrives certain number of times, when foreign matter content is higher, need carries out the resin deironing again to mother liquor and handle, or use it for anything else in addition.Wherein said solid-liquid separation can adopt the routine operation method, uses spinning or vacuum belt filter.
In the step e) according to the invention, at 900-1200 ℃, preferable range is 950-1100 ℃ and carries out calcining and decomposing, obtains the metallurgical-grade aluminum oxide product with the crystal aluminum chloride product that obtains in the step d).Said calcining can be adopted one-part form calcining or sectional calcining.One-part form calcining be with the crystal aluminum chloride direct heating to 900-1200 ℃, calcination time 1-4 hour, obtain alumina product after the thermolysis; The sectional calcining is at first crystal aluminum chloride to be heated 1-2 hour at 300-500 ℃, and most of crystal aluminum chloride is decomposed, and is warming up to 900-1200 ℃ of calcining 1-3 hour then, obtains alumina product.The hydrogen chloride gas that thermolysis produces is formulated as hydrochloric acid after the absorption tower internal recycle absorbs, in acid is dissolved, reuse.
The present invention also provides a kind of wash-out renovation process of macroporous type resin cation(R.C.), and wash-out renovation process according to the invention comprises:
1) saturated macroporous type resin cation(R.C.) water or the hydrochloric acid of absorption in the aforesaid method step c) is carried out wash-out as eluent, wherein, the concentration of hydrochloric acid is 2-10wt%;
2) the macroporous type resin cation(R.C.) behind the wash-out in the step 1) is regenerated with the hydrochloric acid of 2-10wt% concentration.
Wherein, the concentration of preferred hydrochloric acid is 2-10wt% in the step 1).Elution requirement is: eluting temperature is 20 ℃-60 ℃, and the eluent consumption is a 1-3 times of resin volume during wash-out, the eluent flow velocity be 1-3 times of resin volume/hour, eluent passes through resin column with the enterprising mode that goes out down during wash-out.
Wherein, Step 2) adopt the hydrochloric acid of 2-10wt% to regenerate the macroporous type resin cation(R.C.) behind the step 1) wash-out in; Preferred regenerated condition is: the above and then mode that go out down of hydrochloric acid is through macroporous cation type resin column; Regeneration temperature is 20 ℃-60 ℃, and the consumption of hydrochloric acid is a 1-2 times of resin volume, the flow velocity of hydrochloric acid be 1-3 times of resin volume/hour.Recover adsorptive power through regenerated macroporous type resin cation(R.C.).
Compared with prior art, the beneficial effect that the present invention had is that production technique is simple, production process is easy to control, alumina extraction ratio is high, low, the constant product quality of production cost.The present invention selects for use has highly active circulating fluid bed coal ash as raw material, adopts the method that directly acid is dissolved from flyash, to leach aluminum oxide, has omitted yellow soda ash high-temperature calcination activation step, thereby has simplified technical process, and reduced production cost; In addition, owing to there is not the adding of alkali, avoided the introducing of sodium oxide impurity; Adopt acid-resistant reacting kettle (100-200 ℃) under middle temperature to leach during acidleach, the leaching rate of aluminum oxide is high, reaches more than 80%; Adopt magnetic separation and the deironing of resin absorption bonded method, compare with the technology of alkaline process deironing in the past, this method operation steps is simple, production cost is low, good iron removal effect.The resulting alumina product of the method that the present invention relates to, its Al
2O
3Content is not less than 98.9wt%, Fe
2O
3Content is not higher than 0.004wt%, SiO
2Content is not higher than 0.02wt%, Na
2O content is not higher than 0.008wt%, all reaches or is higher than in the People's Republic of China's non-ferrous metal industry standard " YS/T274-1998 aluminum oxide " purity requirement to the metallurgical-grade aluminum oxide first grade.Fe wherein
2O
3And Na
2O content is than the low several times of 0.02wt%, 0.5wt% of standard.
In addition, adopt magnetic plant of the present invention, the iron removal effect has improved more than 20%; Effective clearance of iron brings up to 80% by original 60%; This has greatly alleviated the pressure of deironing in the subsequent technique solution, thereby has reduced production cost, has improved production efficiency.
Description of drawings
Fig. 1 is the process flow sheet for preparing metallurgical-grade aluminum oxide with circulating fluid bed coal ash;
Fig. 2 is the structural representation that is used for the vertical-ring magnetic separator of deferrization of pulverized coal ash.
Embodiment
Pass through embodiment further explain method provided by the present invention below, but therefore the present invention does not receive any restriction.
Raw material adopts certain heat power plant's output circulating fluid bed coal ash, and its chemical ingredients is as shown in table 1.
Table 1 circulating fluid bed coal ash chemical ingredients (wt%)
SiO2 |
Al
2O
3 |
TiO
2 |
CaO |
MgO |
TFe
2O
3 |
FeO |
K
2O
|
Na
2O
|
LOS |
SO
3 |
Summation |
34.70 |
46.28 |
1.48 |
3.61 |
0.21 |
1.54 |
0.22 |
0.39 |
0.17 |
7.17 |
1.32 |
95.77 |
Embodiment 1
(1) gets the fluid bed powder coal ash; Be crushed to 200 orders, add water and process the slurry that solid content is 33wt%, use embodiment 12 to be used for the vertical-ring magnetic separator of deferrization of pulverized coal ash; In field intensity is magnetic separation twice under 1.5 ten thousand GS, after the press filtration of plate basket pressure filter, obtains the filter cake that solid content is 37.5wt%;
(2) in filter cake, adding concentration is that the technical hydrochloric acid of 28wt% carries out acid and dissolves and react; In the hydrochloric acid in HCl and the flyash mol ratio of aluminum oxide be 5: 1; 150 ℃ of temperature of reaction, reaction pressure 1.0MPa, reaction times 2h; Reaction product obtains pH value and is 1.5 salt pickling liquor after the press filtration of plate basket pressure filter, washing;
(3) with the salt pickling liquor after heat exchange is cooled to 65 ℃, with the resin column of D001 (Wan Dong chemical plant, Anhui) resin is housed, carry out deironing with the mode of single-column, during processing salt pickling liquor flow velocity be 2 times of resin volumes/hour, obtain refined crystalline aluminium chloride liquid;
After said macroporous type resin cation(R.C.) absorption is saturated; Make resin recover adsorptive power through wash-out and regeneration; Elution requirement is: it is the hydrochloric acid of 4wt% that eluent adopts concentration; Eluting temperature is 50 ℃, the hydrochloric acid flow velocity be 1 times of resin volume/hour, adopt the eluent of 2 times of resin volumes to carry out wash-out altogether; Adopting concentration during regeneration is the hydrochloric acid of 4wt%, and temperature is 40 ℃, the hydrochloric acid flow velocity be 2 times of resin volumes/hour, adopt the hydrochloric acid of 1 times of resin volume to regenerate altogether.
(4) refined crystalline aluminium chloride liquid is carried out evaporation concentration, pressure is-0.05MPa when concentrating, 80 ℃ of thickening temperatures, and through concentrating postcooling, crystallization, the crystal weight that control is separated out accounts for 50% of the former weight of refined crystalline aluminium chloride liquid, obtains crystal aluminum chloride through spinning.
(5) step (4) gained crystal aluminum chloride was calcined 2 hours at 400 ℃, 1100 ℃ of calcinings 2 hours, obtained aluminum oxide then.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 2
Except that step (1), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (1) is adjusted into:
Get the fluid bed powder coal ash; Be crushed to 300 orders, add water and process the slurry that solid content is 25wt%, use embodiment 12 to be used for the vertical-ring magnetic separator of deferrization of pulverized coal ash; In field intensity is magnetic separation three times under 1.0 ten thousand GS, after the press filtration of plate basket pressure filter, obtains the filter cake that solid content is 32.0wt%;
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 3
Except that step (1), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (1) is adjusted into:
Get the fluid bed powder coal ash; Be crushed to 150 orders, add water and process the slurry that solid content is 40wt%, use embodiment 12 to be used for the vertical-ring magnetic separator of deferrization of pulverized coal ash; In field intensity is magnetic separation two times under 2.0 ten thousand GS, after the press filtration of plate basket pressure filter, obtains the filter cake that solid content is 43.0wt%;
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 4
Except that step (2), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (2) is adjusted into:
(2) in filter cake, adding concentration is that the technical hydrochloric acid of 20wt% carries out acid and dissolves and react; In the hydrochloric acid in HCl and the flyash mol ratio of aluminum oxide be 9: 1; 200 ℃ of temperature of reaction, reaction pressure 2.1MPa, reaction times 2h; Reaction product obtains pH value and is 1.4 salt pickling liquor after settlement separate, washing;
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 5
Except that step (2), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (2) is adjusted into:
(2) in filter cake, adding concentration is that the technical hydrochloric acid of 37wt% carries out acid and dissolves and react; In the hydrochloric acid in HCl and the flyash mol ratio of aluminum oxide be 4: 1; 110 ℃ of temperature of reaction, reaction pressure 0.15MPa, reaction times 2h; Reaction product obtains pH value and is 1.7 salt pickling liquor after filtration under diminished pressure, washing;
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 6
Except that step (3), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (3) is adjusted into:
(3) with the salt pickling liquor after heat exchange is cooled to 90 ℃; With the resin column that 732 (Anhui Samsung resin Science and Technology Ltd.) resin is housed; Mode with twin columns polyphones is carried out deironing, during processing salt pickling liquor flow velocity be 4 times of resin volumes/hour, obtain refined crystalline aluminium chloride liquid;
After said macroporous type resin cation(R.C.) absorption is saturated; Make resin recover adsorptive power through wash-out and regeneration, elution requirement is: eluent adopts water, and eluting temperature is 60 ℃; Water flow velocity be 1 times of resin volume/hour, adopt the eluent of 3 times of resin volumes to carry out wash-out altogether; Adopting concentration during regeneration is the hydrochloric acid of 6wt%, and temperature is 50 ℃, the hydrochloric acid flow velocity be 3 times of resin volumes/hour, adopt the hydrochloric acid of 2 times of resin volumes to regenerate altogether.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 7
Except that step (3), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (3) is adjusted into:
(3) with the salt pickling liquor after heat exchange is cooled to 30 ℃, with the resin column of JK008 (Wan Dong chemical plant, Anhui) resin is housed, carry out deironing with the mode of twin columns polyphone, during processing salt pickling liquor flow velocity be 4 times of resin volumes/hour, obtain refined crystalline aluminium chloride liquid;
After said macroporous type resin cation(R.C.) absorption is saturated; Make resin recover adsorptive power through wash-out and regeneration; Elution requirement is: it is the hydrochloric acid of 8wt% that eluent adopts concentration; Eluting temperature is 30 ℃, the hydrochloric acid flow velocity be 2 times of resin volumes/hour, adopt the eluent of 1 times of resin volume to carry out wash-out altogether; Adopting concentration during regeneration is the hydrochloric acid of 2wt%, and temperature is 20 ℃, the hydrochloric acid flow velocity be 2 times of resin volumes/hour, adopt the hydrochloric acid of 1 times of resin volume to regenerate altogether.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 8
The employed resin of step (3) among the embodiment 7 is changed to SPC-1 (Shanghai Resin Factory) resin, and other processing condition are constant.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 9
Except that step (4), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (4) is adjusted into:
(4) refined crystalline aluminium chloride liquid is carried out evaporation concentration, pressure is-0.03MPa when concentrating, and 95 ℃ of thickening temperatures concentrate postcooling, crystallization, and the crystal weight that control is separated out accounts for 40% of the former weight of refined crystalline aluminium chloride liquid, obtains crystal aluminum chloride through filtration under diminished pressure.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 10
Except that step (5), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (5) is adjusted into:
(5) crystal aluminum chloride that obtains in the step (4) was directly being obtained alumina product in 3 hours 1200 ℃ of calcinings.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
Embodiment 11
Except that step (5), other operating procedure conditions are all identical with embodiment 1.Operating procedure condition in the step (5) is adjusted into:
(5) step (4) gained crystal aluminum chloride was calcined 2 hours at 500 ℃, 950 ℃ of calcinings 2 hours, obtained aluminum oxide then.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
The comparative example 1
Step (1) is omitted with embodiment 1 in step (2), (3), (4), (5), and directly acid is molten without magnetic separation to be about to flyash, obtains alumina product.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
The comparative example 2
Step (3) is omitted with embodiment 1 in step (1), (2), (4) (5), is about to salt pickling liquor directly condensing crystal, calcining without the resin absorption deironing, obtains alumina product.
Through measuring, the chemical ingredients of alumina product is as shown in table 2.
The chemical ingredients of table 2 alumina product
Annotate: Al
2O
3Content is 100% to deduct the surplus of listed impurity summation in the table.
Embodiment 12 vertical-ring magnetic separators
As shown in Figure 2, vertical-ring magnetic separator of the present invention comprises: change 101, induction medium 102, upper yoke 103, lower yoke 104, magnet coil 105, opening for feed 106 and mine tailing bucket 107 also comprise pulsing mechanism 108 and flushometer 109.
Change 101 is the annular carrier, wherein is loaded with induction medium 102, during change 101 rotations, drives the motion of matter of induction medium 102 and induction medium 102 absorption, so that accomplish the material sorting.Change 101 can be processed by any suitable material, for example carbon steel etc.
Motor or other drive units can provide power for change 101, make change 101 to rotate according to setting speed.
When parameters such as the iron-holder of material or treatment capacity are lower than preset value, adopt lower rotating speed, for example 3 rev/mins, ferromegnetism impurity and magnetic field are fully acted on, and be adsorbed to induction medium and select on the net.
Induction medium 102 is installed in the change; The magnetic field that magnet coil 105 produces makes upper yoke 103 and lower yoke 104 become a pair of generation vertical direction field pole; Upper yoke 103 and lower yoke 104 are arranged on the inside and outside both sides of change 101 belows, so that change 101 vertical rotating between magnetic pole.When change 101 rotations, the induction medium 102 in the change 101 can be through the pole pair magnetization deironing of upper yoke 103 and lower yoke 104 formations.
Said induction medium 102 is the Composite Steel expanded metals.XPM is processed by 1Cr17.Every layer of XPM weaved into by the silk stalk, and grid is a rhombus.The edge of said silk stalk has rib shape wedge angle, and said upper yoke 103 is connected with opening for feed 106, and said lower yoke 104 is connected with the mine tailing bucket 107 that is used for discharging.The medium layer spacing of XPM is for being 3mm.Magnet coil 105 is a double glass fiber bag enameled aluminium flat wire, and said double glass fiber bag enameled aluminium flat wire is to be solid conductor, and magnet coil 105 electric currents adopt continuous adjustable control, thereby magnetic field is also adjustable continuously.
Vertical-ring magnetic separator also comprises pulsing mechanism 108, and said pulsing mechanism 108 links to each other with mine tailing bucket 107 through rubber eardrum 111.Said pulsing mechanism is realized that by eccentric rod gear pulsing mechanism 108 links to each other with mine tailing bucket 107, thereby the alternating force that pulsing mechanism 108 is produced promotes 111 to-and-fro movements of rubber eardrum, can be so that the ore pulp in the mine tailing bucket 107 produces pulsation.
Flushometer 109 is positioned at the top of change 101, is used for utilizing current that magnetic material is poured the concentrate bucket.Flushometer 109 can be various suitable baths, spray equipment, for example shower nozzle, water pipe etc.
Said opening for feed 106 is connected with the sidepiece of upper yoke 103, so that flyash is from the sidepiece inflow of change.Opening for feed 106 can make hopper or feed-pipe.Be used to get into upper yoke 103 with less drop, avoided magnetic-particle owing to the phenomenon that action of gravity sees through induction medium 102 takes place, thereby improved the effect of magnetic separation removal of impurities into the opening for feed 106 in ore deposit.
Said vertical-ring magnetic separator also comprises refrigerating unit 112, and said refrigerating unit 112 is arranged on around the magnet coil, is used to reduce the working temperature of magnet coil, and said refrigerating unit is for all pressing the chamber water jacket.
All press the chamber water jacket to adopt stainless material to process, less scaling.Owing to all install at the Inlet and outlet water place of water jacket and all to press the chamber, the said chamber of all pressing has guaranteed water each layer water jacket of flowing through equably, and in cover, is full of everywhere.Thereby prevent the short out road of partial water, the influence heat radiation.The water channel cross-sectional area of every layer of water jacket is very big, can avoid incrustation scale to stop up fully, even there is a place to stop up, does not also influence the proper flow of recirculated water in the water jacket.And water jacket closely contacts with the coil big area, can most of heat that coil produces be taken away through current.
All press the chamber water jacket to compare with common hollow copper tubing heat radiation, radiating efficiency is high, and winding temperature rise is low, and the equipment exciting power is low.At rated exciting current is under the situation of 40A, compares with the magnetic separator that adopts common hollow copper tubing heat radiation, and exciting power can be reduced to 21kw by 35kw.
When utilizing magnetic plant of the present invention to work; 103 slit flow is through change 101 from sidepiece along upper yoke for the ore pulp of charging, because the induction mediums 102 in the change 101 are magnetized in background magnetic field, induction medium 102 surfaces form the high magnetic fields of gradients; In the ore pulp magnetic-particle under this high the action of a magnetic field sorption on induction medium 102 surfaces; And rotate with change 101, and brought to the no field regions at change 101 tops, wash by water through the flushometer 109 that is arranged in the top again magnetic material is poured the concentrate bucket; Non-magnetic particle then flows in the mine tailing bucket 107 along the slit of lower yoke 104, and then is discharged by the mine tailing mouth of mine tailing bucket 107.